I work on a commercial application that is developed using Visual Studio 2010 Isolated Shell. Being an extensibility solution, our application reuses standard toolbars that come from the Isolated Shell framework. I am now trying to migrate the whole application code base from VS 2010 to VS 2015. All the projects seem to have migrated and the builds are also succeeding in VS 2015. However, when I open our application for debugging, the icons on the standard and Debug toolbars don't appear. The same issue occurs when I install the application from the Release Mode installer (.msi) and open it. The buttons on the toolbars work fine when I click. I am attaching 2 image below. The first one is from our application built on VS 2010. All the icons appear and work as expected. The second image is from our application built on VS 2015. As you can see, many icons such as Add New Item, Save, Save All, Open File etc. are all missing.
I searched online to see if someone else faced a similar issue. But none that are helpful.